Object progression path prediction devices are known that change positions that an object might take with the passage of time, generate a spatiotemporal trajectory, and perform probability prediction of the progression path of the object (Japanese Patent Application Laid-Open (JP-A) No. 2007-233646). In such an object progression path prediction device, a trajectory is generated that can secure safety under conditions that might arise in reality.
Moreover, an online risk training system is known in which the system autonomously trains with experience in actual environments, and is capable of ascertaining the dangerousness of multiple external environments (JP-A No. 2008-238831). This online risk training system is realized to automatically extract feature amounts of images and learn their relationships to driving operations of a driver.
Moreover, a crossroad collision prevention device is known that prevents vehicle collisions by warning a driver when a vehicle is in a situation with a high danger of collision at a crossroad or traffic merge point (JP-A No. 2005-173703). This crossroad collision prevention device is realized by holding a database of accident states at crossroads, and performing searches and applying scoring based on sensor data.